Method for improving safety of voltage regulator

Abstract

A method for improving safety of voltage regulator is disclosed. In order to improve safety of a voltage regulator, a MOS-FET is disposed on a source power lane that receives power supplied from a DC power supply. A set of voltage regulators is connected to a set of fork power lanes, correspondingly, branching off from the source power lane. PTC thermistors are disposed on a surface or in the vicinity of semiconductor chips of the voltage regulators. When temperature at any one of the PTC thermistors increases, a protection controller turns off the MOS-FET. When temperature detected by a temperature sensor incorporated within the semiconductor chip has increased, each of the voltage regulators turns off the MOS-FET via a base management controller.

What is claimed is: 
     
       1. A power-supply system comprising:
 a protection switch disposed on a power lane receiving power from a DC power supply; 
 a plurality of voltage regulators, wherein one of said voltage regulators includes a switching element located within a semiconductor chip, and branching off from said power lane; 
 a first temperature sensor, located within said semiconductor chip, for detecting temperature of said one voltage regulator; 
 a second temperature sensor arranged on a surface of said semiconductor chip; and 
 a controller for turning off said protection switch when one of said first and second temperature sensors detects a temperature increase, and for stopping power supplied to said plurality of voltage regulators. 
 
     
     
       2. The power-supply system of  claim 1 , wherein said protective switch inhibits incoming current when said controller stops power supplied to said voltage regulators. 
     
     
       3. The power-supply system of  claim 1 , wherein said voltage regulators send a signal to turn off said protection switch in response to an abnormality for ON/OFF resistances of said switching elements. 
     
     
       4. A sub-system for a computer comprising:
 a processor and a system memory; 
 a protection switch disposed on a power lane receiving power from a DC power supply; 
 a plurality of semiconductor chips for supplying power, each received from said power lane including a switching circuit; 
 a plurality of voltage regulators, wherein one of said voltage regulators includes a switching element to supply power to said processor and said system memory, and branching off from said power lane; 
 a first temperature sensor for detecting temperature of said voltage regulators; and 
 a first protection circuit containing a first temperature sensor that detects temperature inside said semiconductor chip; 
 a second protection circuit including a second temperature sensor that detects the surface temperature of said semiconductor chip; and 
 a controller that makes said protective switch an OFF state according to temperature which said first protection circuit or said second protection circuit detected.